Such an electric lamp is known from WO2008154172. In the known lamp a semiconductor light source, i.e. a plurality of LEDs, is mounted on one of the cooling fins. Both the light source and the cooling fins are arranged in a lamp bulb, the lamp bulb having a lamp shell with a shape according to the lamp bulb of a common incandescent general light source (GLS). The known lamp has the disadvantage that cooling of the LEDs is not effective as the cooling fins are arranged in a fully closed lamp shell. Once the filling of the bulb has been warmed up by the heat generating LEDs inside the bulb, transport of heat from inside the bulb to the exterior has to occur through the lamp shell, said shell generally not being a good heat conductor. In the known lamp, to enhance heat flow from the LEDs to the ambient atmosphere, the lamp is provided with a heat conductor inside the shell, causing the lamp to be of a relatively complex construction. In the known lamp the shell is filled with a liquid or a gel to counteract the detrimental effect of the shell on heat conduction, but this results in the lamp having the additional disadvantage of being relatively heavy. Furthermore, as the heat still has to be transported through the relatively poorly heat conducting wall of the shell, the known lamp still has a relatively high temperature inside the bulb, causing the lamp to have a relatively low efficiency as the operation of the LEDs at higher temperatures is relatively inefficient.